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<A NAME="pgfId-276632"></A>DESTINATION_ORDER</H4>
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<A NAME="pgfId-274762"></A>The DESTINATION_ORDER QoS policy controls the order in which samples within a given instance are made available to a data reader. If a history depth of one (the default) is specified, the instance will reflect the most recent value written by all data writers to that instance. Here is the IDL for the Destination Order Qos:</LI>
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<A NAME="pgfId-275111"></A>&nbsp;</P>
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<A NAME="pgfId-275182"></A>enum DestinationOrderQosPolicyKind {</P>
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<A NAME="pgfId-275183"></A>  BY_RECEPTION_TIMESTAMP_DESTINATIONORDER_QOS,</P>
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<A NAME="pgfId-275184"></A>  BY_SOURCE_TIMESTAMP_DESTINATIONORDER_QOS</P>
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<A NAME="pgfId-275185"></A>};</P>
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<A NAME="pgfId-275234"></A>&nbsp;</P>
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<A NAME="pgfId-275210"></A>struct DestinationOrderQosPolicy {</P>
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<A NAME="pgfId-275211"></A>  DestinationOrderQosPolicyKind kind;</P>
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<A NAME="pgfId-275212"></A>};</P>
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<A NAME="pgfId-275166"></A>&nbsp;</P>
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<A NAME="pgfId-274767"></A>The <EM CLASS="Code">
BY_RECEPTION_TIMESTAMP_DESTINATIONORDER_QOS</EM>
 value (the default) indicates that samples within an instance are ordered in the order in which they were received by the data reader. Note that samples are not necessarily received in the order sent by the same data writer. To enforce this type of ordering, the <EM CLASS="Code">
BY_SOURCE_TIMESTAMP_DESTINATIONORDER_QOS</EM>
 value should be used.</LI>
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<A NAME="pgfId-274773"></A>The <EM CLASS="Code">
BY_SOURCE_TIMESTAMP_DESTINATIONORDER_QOS</EM>
 value indicates that samples within an instance are ordered based on a timestamp provided by the data writer. It should be noted that if multiple data writers write to the same instance, care should be taken to ensure that clocks are synchronized to prevent incorrect ordering on the data reader.</LI>
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